Chase Blackburn's only job after the lockout was teaching math. But a few variables went his way, and now he's working on Roman numerals.

INDIANAPOLIS — Chase Blackburn can work through all sorts of mathematical equations, but his own NFL career dilemma just didn't add up.

Although he was the leading tackler on special teams in his first six seasons with the Giants and a team captain last season, his phone never rang when the lockout ended in the summer. The reserve linebacker had figured that if the Giants didn't re-sign him, another team would. So he waited. And waited.

Days turned to weeks, weeks became months, and eventually reality sank in. Blackburn, a married father of two young boys, had to get on with his life.

He lined up a gig as a long-term substitute math teacher at a middle school in Dublin, Ohio.

Then, about two months ago, came the call. Giants rookie linebacker Mark Herzlich had suffered a badly sprained ankle in a loss to the Saints, and the team didn't have a lot of depth at the position. Michael Boley had been sidelined with a hamstring injury, and rookie middle linebacker Greg Jones had very little experience.

So the Giants brought back Blackburn, who will start at middle linebacker in Super Bowl XLVI.

Turns out it wasn't a pipe dream for Blackburn to keep a suitcase packed in his bedroom for just such an occasion -- a bag containing the bare necessities: jeans, shorts, some dress shirts, T-shirts and underwear, and a hanging business suit to wear while traveling.

"I'm a pretty optimistic person," Blackburn said. "I do have that quality going for me. I have a good amount of perseverance. I just kept praying to get an opportunity -- my wife and I prayed -- and I wanted to be ready when the opportunity did present itself."

That bag aside, he and his wife, Meghan, were prepared to settle down in Ohio with their sons, a 2-year-old and an infant. The couple had borrowed a trailer from Blackburn's father and filled it with all their worldly possessions, hoping they would move it to wherever Chase signed. As time passed, they slowly emptied the trailer and began to put down roots.

"It was disappointing and unexpected," said Blackburn, who in a way relived his experience as a rookie, when he went undrafted, wasn't signed immediately after the draft and only made the team after taking full advantage of his opportunity to impress coaches at mini-camp.

"I knew if I got the opportunity [after the lockout], I'd make the most of it again," he said. "But it's humbling to think that I thought I had done something. I'd worked my way up from undrafted free agent to playing, and to not get a call from anybody was a little disheartening.

"If I didn't get the call this year, I was going to work my butt off and try to get into training camp next year."

The Giants are glad nobody signed him in the interim.

"From the moment he arrived, it was like he never left," Coach Tom Coughlin said. "He absorbed where we were really fast, jumped right back into special teams, jumped into the linebacker role, and progressed."

Obviously, the teaching job is on ice for now.

His would-be employer understands -- the education major with a math degree from the University of Akron doesn't need to begin his second career quite yet.